000 AXNT20 KNHC 131619 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Mon Mar 13 2023 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1200 UTC surface analysis and satellite imagery through 1615 UTC. ...SPECIAL FEATURES... Atlantic Swell Event: A cold front enters the forecast waters near 31N46W and continues southwestward to 24N57W then westward to near 23N68W. Winds have dropped below gale-force as of 09Z, but seas remain elevated. Large NW swell trailing the front is producing seas of 16 to 23 ft across this area. A recent scatterometer pass reveals fresh to strong westerly winds behind the front north of 29N while fresh to strong SW winds are noted ahead of the front north of 25N and west of 37W. Seas north of 24N and east of 70W will remain 12 ft and higher in N to NE swell through early Tue. Scattered moderate convection is observed on satellite imagery along and ahead of the front north of 25N and west of 40W. This active weather is expected to shift eastward with the front through this afternoon Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details on the large swell event. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic through Sierra Leone near 08N13W, then continues SW to 05N17W then westward to 05N20W. The ITCZ continues from 05N20W to the coast of northeastern Brazil near 02S39W. Scattered moderate convection is noted from 02N southward between 16W and 34W. GULF OF MEXICO... A cold front stretches across the basin from near Apalachee Bay, Florida to near Tamaulipas, Mexico. Fresh to strong NE winds are observed behind the front, along with seas of 5 to 7 ft and up to 8ft across the coastal waters of Texas. Scattered moderate convection is along the front across the Florida coastal waters extending into the Big Bend. Moderate SE winds and seas of 4 to 6 ft are found ahead of the front. The exception being in the southeast Gulf, where seas are 2 to 4 ft near a weak low, spinning offshore the Mexican coast near 21N95W. No convection is observed with this feature. For the forecast, fresh to strong NE winds behind the front will reach from Florida Bay to near Veracruz, Mexico by early Tue, gradually washing out over the southern Gulf through early Wed. Return flow will develop by early Thu with fresh to strong winds in the west-central and NW Gulf ahead of the next front, with these winds spreading and dominating the basin by early Fri. The front will move into the NW Gulf Fri morning, quickly reaching from Apalachee Bay, Florida to the central Bay of Campeche late Fri night. Gale-force winds will be possible offshore Tamaulipas and Veracruz behind the front. CARIBBEAN SEA... Fair and stable conditions exist across the Caribbean basin. Gentle to moderate trades prevail across the basin south of 20N and east of 80W, while fresh to locally strong SE to S winds are west of 80W, and opening up into the Gulf of Mexico. Seas are generally 4 to 6 ft across the basin, with areas up to 7 ft in the eastern Caribbean and in the Gulf of Honduras. For the forecast, fresh to strong SE winds north of Honduras will diminish this afternoon. Otherwise, a weak pressure pattern is yielding below normal tradewinds across most of the basin. Tradewinds will increase slightly tonight through Wed. New northerly swell will reach the Atlantic waters early Tue and move through the northeast Caribbean Passages. A cold front is forecast to sink S to SE across the northwestern basin Wed, reach from the Windward Passage to northern Gulf of Honduras Thu, and from the northern Leeward Islands to NE coast of Honduras Fri. Fresh to strong winds will follow the front, with N swell spreading through Atlantic passages. ATLANTIC OCEAN... Please see the Special Features section for more details on the swell event ongoing in the Central Atlantic. A 1001 mb low pressure off the southeast US coast is moving northeast, dragging the Gulf of Mexico cold front across northern Florida. Fresh to strong S to SW winds are noted in a recent scatterometer pass north of 27N, west of 70W to the coastal waters of north and central Florida. Seas are 7 to 11 ft across these waters in residual NE swell. Scattered moderate convection ahead of the front is observed north of 27N from Florida eastward to 67W. Weak high pressure persists to the east of the Bahamas and the Leeward islands yielding light to gentle anticyclonic winds south of 25N between 60W and 76W. Seas are 5 to 7 ft in NE swell from the Bahamas northeastward, then increase to 8 to 12 ft farther northeast. Farther east, a stationary front is draped across the eastern Atlantic from 31N19W to 25N42W. Scattered moderate convection is observed within 100 nm on either side of the boundary. Large northerly swell generated well north of the area in recent days continues to spread across most of the regional Atlantic waters from 05N to 27N between and east of 55W with seas in the 6 to 10 ft range. Seas directly behind the front are currently 8 to 10 ft east of 40W. A weak ridge situated southeast of the boundary is producing moderate to locally fresh NE trades across the remainder of the tropical Atlantic. For the forecast W of 55W, the weakening cold front from near 25N55W to the southeast Bahamas will stall and dissipate west of 60W later today. Strong westerly winds north of 28N and large seas across the waters will prevail behind the front today before winds diminish. Another cold front will enter the far northwest waters today, then continue southeast with fresh to strong winds north of 27N behind it, with the front reaching the northwest Bahamas Tue morning, from near 28N55W to the Windward Passage Thu morning, and from 20N55W through the Leeward Islands by Fri morning. Large N swell will accompany the second front with seas of 12 ft or greater north of 25N and east of 72W. $$ Nepaul